Salah Abdeslam, the prime surviving suspect in November's Paris attacks, answered questions from Belgian investigators on Saturday a day after his arrest but will fight extradition to France, his lawyer said.
He had planned to blow himself up on Nov. 13 at the Stade de France, but changed his mind, the Paris prosecutor said.
"Salah Abdesalam today during questioning by investigators affirmed that, and I quote, 'he wanted to blow himself up at the Stade de France and that he had backed down'," Francois Molins told reporters, adding that Abdeslam's initial statements should be treated with caution.
Belgian prosecutors said Abdeslam and a second man arrested with him on Friday had been charged with "participation in terrorist murder".
"He is cooperating with Belgian justice," his lawyer Sven Mary told reporters outside the judicial police headquarters, adding that Abdeslam, bedridden after being shot in the leg during his capture, admitted being in Paris on Nov. 13.
His elder brother was among the suicide bombers involved in gun and bomb attacks that night that killed 130 people.
Mary added that the 26-year-old French national, who was born and raised in Brussels in a Moroccan immigrant family, would refuse the extradition demanded by French President Francois Hollande, who was in Brussels during Friday's drama.
Legal experts said his challenge was unlikely to succeed, but it would buy him more time to prepare his eventual defence.
Having spent his first night in captivity in a Brussels hospital, he is expected to be moved to a high-security jail in the western city of Bruges while legal proceedings continue.
French and Belgian leaders have hailed his arrest, several days after Brussels police stumbled on his fingerprints during a raid that turned violent, as a turning point in clarifying who planned and ordered the Paris attacks, in which all the identified assailants were shot dead or blew themselves up.
It may also be an opportunity to disrupt other militant cells which Belgian Foreign Minister Didier Reynders said were certainly "out there" and planning further violence.
"We've won a battle against the forces of ignorance but the struggle isn't over," Belgian Prime Minister Charles Michel said.
Interpol issued an advisory to ensure border guards were ready to seize fleeing accomplices. A Belgian, 31-year-old Mohamed Abrini, is still on EU police agency Europol's "Most Wanted" list after being caught on CCTV with Abdeslam in a car heading to the French capital two days before the attacks.
The arrest raises questions about the intelligence capabilities of the security services and the size of network Abdeslam could call on to conceal him for four months before he was found just a few hundred yards from his parents' home in the down-at-heel, North African quarter of the borough of Molenbeek.
A man using false papers in the names of Amine Choukri and Monir Ahmed Alaaj was also charged with terrorist murder. As Choukri, he was documented by German police at Ulm in October when he was stopped in a car with Abdeslam. A man in the house was charged with belonging to a terrorist organisation and he and a woman were charged with concealing criminals.
While it is unclear exactly where Abdeslam has been since he called two acquaintances in a panic in the hours after the attacks and asked them to drive to Paris and bring him home, it appears he was in the Belgian capital all or most of the time.
Security agencies' difficulties in pursuit of Belgium's unusually high number of citizens fighting in Syria, has been a key factor in the inquiry, along with arms dealing in Brussels.
As Parisians, and families of the victims, voiced relief at the arrest, French Interior Minister Bernard Cazeneuve said after an emergency cabinet meeting that a trial could answer questions for those who suffered in the attacks.
"Abdeslam will have to answer to French justice for his acts," he said. "It is an important blow to the terrorist organisation DAESH in Europe."
A trickle of people came to a makeshift memorial in Paris that has engulfed the monument at Place de la Republique, near the scene of much of the bloodshed, to pay their respects.
"It's really a relief," said Emilien Bouthillier, who works in the neighbourhood. "I can't wait for Belgium to transfer and return him to France so he can be tried the way he should be."
Friday's heavily armed swoop came after fake passports and Abdeslam's fingerprints were found following a bloody raid on Tuesday in which Mohamed Belkaid, a 35-year-old Algerian was shot dead and police officers wounded.
Near the scene of the arrest, newsagent Dominique noted that Abdeslam had been well known to him and many in the community.
"He was a very nice lad before," he said. "How can things go this far? That's really something else."
His elder brother Brahim, a Brussels barkeeper who shared a chequered history of drugs and petty crime, blew himself up outside a Parisian cafe on the night of the attacks.
Hollande said the younger man's role in the killings was unclear, but investigators were sure he helped plan the operation for the Syria-based group.
There has also been speculation, associated with the finding of an abandoned suicide vest in Paris and the apparent panic of Abdeslam in calling friends to pick him up, that the younger brother had been meant to kill himself, but changed his mind.
A four-month inquiry that had seemed to go cold, heated up when French and Belgium officers went to an apartment in the southern Brussels suburb of Forest on Tuesday.
Thinking they were simply looking for physical evidence, they were instead confronted by at least two people spraying automatic gunfire at them as they opened the door.
Then on Friday, local media said, a tapped telephone confirmed that Abdeslam was in the house in rue des Quatre-Vents in Molenbeek. After French media broke word that Abdeslam's fingerprints had been found, police moved in and seized him.